During flight training I was taking a C172 VFR from Fort Pierce to Ket West. Callsign N1247M. Everyone I Spoke to had problems and keep thinking I was calling 1347M. In fact it got so annoying that I adopted the callsign N1347M to make things easier. There was so much airtime being taken up that I felt it was less stressful to become a tree instead of a two. Three was never a safety issue under vfr and I think I might even have enhanced safety around busy terminal areas by minimising RT.